Browse All Free Tools

Focused formulas—health, money, grades, tips, science—each on its own page. Treat results as helpful estimates; use professional advice when health, tax, or legal outcomes really matter.

• AC BTU CalculatorWhat size air conditioner do I need? Estimate room AC BTUs, tons, and a common unit size from square footage—adjust for sun, people, and kitchen. Free planning estimate.
• Age Difference Calculator — Exact Age Gap in Years, Months & DaysEnter two birthdays to see who is older and the exact age gap in years, months, and days—plus how many days apart. Free, private, no signup.
• Average CalculatorPaste numbers (commas, spaces, or new lines) and get the arithmetic mean instantly—plus sum, count, min, max, and range, with calculation steps. Free, private, no signup.
• Biweekly Paycheck CalculatorEstimate biweekly gross and take-home from hourly rate, hours, overtime, and a flat tax %. 26 paychecks a year. Planning only—free, no signup.
• BMI CalculatorFree adult BMI from height and weight (kg/cm or lb/ft/in). WHO categories, healthy weight range, optional Asia-Pacific & waist. Screening only—runs in your browser.
• Body Fat CalculatorCalculate body fat % with the US Navy tape method or BMI. Waist, neck, hips, fat & lean mass. Free, private, metric & imperial.
• Break-Even CalculatorFree break-even calculator — find break-even units and revenue from fixed costs, price, and variable cost. Includes contribution margin and targets. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Breaker Size Calculator — Watts, Amps & Wire MatchFind a standard breaker from watts or amps with the 125% continuous-load rule and typical copper wire pairing. Free US DIY estimate—runs locally in your browser.
• Brine Calculator — Wet, Dry & Equilibrium Salt MathFind salt grams for any brine %. Wet, dry, and equilibrium modes with US gallons/quarts and liters. Salt-type cup estimates—weigh grams for accuracy.
• Cake Pan ConverterFree cake pan converter: rectangular and round pans → area ratio and batter scale factor. Swap 9×13 for 8×8 or round tins. Runs locally in your browser.
• Calorie CalculatorEstimate daily calories using the Mifflin-St Jeor BMR formula and TDEE activity multipliers for maintenance, weight loss, or weight gain. Runs locally in your browser when supported—no upload required for normal use.
• Carpet CalculatorFree carpet calculator: room size + roll width → square yards and linear feet with seaming waste. Bedroom and living presets, 12 ft roll width. Runs locally in your browser.
• Charity CalculatorFree charity calculator for donation budgeting: percent-of-income or fixed gifts, formula breakdown, scenario table, gross/net basis. Browser-local — not tax advice.
• Circuit Load CalculatorFree circuit load calculator: sum appliance watts on one breaker → amps and load percentage. 80% guidance for continuous loads. Runs locally in your browser.
• Combination Calculator — nCr (n Choose r)Calculate combinations nCr = n!/(r!(n−r)!) for unordered selections. No upload: runs locally in your browser. Free, instant nCr results.
• Compost CalculatorFree compost calculator: bed or area and depth → cubic yards, cubic feet, liters, and bag counts for amendments and top-dressing. Depth presets and optional buffer. Runs locally in your browser.
• Concrete CalculatorFree concrete calculator: slab footprint + depth → cubic yards and bag counts. Patio, sidewalk, and post-hole presets with ready-mix guide. Runs locally in your browser.
• Cost of Living CalculatorFree cost of living calculator — compare two cities and estimate equivalent salary using cost indices (and optional category weights). Runs locally. No signup.
• Cups to Grams CalculatorConvert cups to grams for baking: flour, sugar, butter, brown sugar, cocoa, and oats. Ingredient-specific US cup weights. Free, instant, no signup.
• Discount Calculator — Sale Price, Savings & Reverse PriceCalculate sale price and savings from percent or fixed discounts. Reverse original price too. No upload—runs locally in your browser. Free.
• Drain Slope CalculatorFree drain slope calculator: horizontal run and slope in/ft → total drop and percent grade with IPC minimum check. Runs locally in your browser.
• Drywall CalculatorFree drywall calculator: room size + wall height → 4×8 sheet count with door/window deductions and waste buffer. Bedroom and basement presets. Runs locally in your browser.
• Duct CFM CalculatorFree duct CFM calculator: AC tonnage or cooling BTU → required supply airflow using 400 CFM per ton. Runs locally in your browser.
• Duct Size CalculatorFree duct size calculator: CFM and velocity → round duct diameter with next standard size. Runs locally in your browser.
• Electricity Cost CalculatorFree electricity cost calculator: kWh = (watts ÷ 1000) × hours; cost = kWh × your $/kWh rate—stack appliances, peak/off-peak. Runs in your browser, no signup.
• Exponent CalculatorCalculate powers like a^b, negative exponents, and fractional exponents with clear results and quick examples like 2^3 = 8. Runs locally in your browser when supported—no upload required for normal use.
• Factorial Calculator — n! (n Factorial)Calculate factorial n! for 0 ≤ n ≤ 500 with exact big-integer results. No upload—runs locally in your browser. Free, instant n! for combinatorics.
• Fascia CalculatorFree fascia board calculator: eave + rake sections → linear feet, waste, and boards to order. Optional material cost. Runs locally in your browser.
• Fence CalculatorFree fence calculator: run length or yard perimeter → panels and posts with waste buffer. Wood and vinyl 8 ft presets. Runs locally in your browser.
• Flooring CalculatorFree flooring calculator: room size + sq ft per box → cartons to buy with waste buffer. LVP and laminate presets, 10–20% waste, imperial and metric. Runs locally in your browser.
• Fraction CalculatorFree fraction calculator with steps: add, subtract, multiply, divide, simplify, and show mixed/decimal forms instantly. Fast, private, no signup. Runs locally in your browser when supported—no upload required for normal use.
• Freelance Rate CalculatorFree freelance rate calculator — turn target income, business expenses, tax, and billable hours into a minimum hourly rate, with optional profit buffer and project price. No signup. Runs locally in your browser when supported—no upload required for normal use.
• French Drain CalculatorFree French drain calculator: trench length, width, and fill depth → cubic yards and bags of drain rock. Foundation and downspout presets, 12–24 in depth guide, order buffer. Imperial or metric. Runs locally in your browser.
• Fuel Cost CalculatorFree fuel cost calculator: trip fuel = distance ÷ MPG (or km × L/100km ÷ 100) × price per gallon or liter—round trip & buffer optional. Private, no signup. Runs locally in your browser when supported—no upload required for normal use.
• Furnace BTU CalculatorFree furnace BTU calculator: room or whole-home sq ft → recommended heating BTU/hr output by climate zone. Runs locally in your browser.
• GCF CalculatorFind the greatest common factor of two or more integers using the Euclidean algorithm and factor-method explanations. Runs locally in your browser when supported—no upload required for normal use.
• Gold Zakat CalculatorFree gold zakat calculator: weight, karat, 24k price—85g nisab & 2.5% if above threshold. Runs locally in your browser; never uploaded. Estimate only.
• GPA Calculator — Grade Points & CreditsCalculate weighted GPA from letter grades and credit hours. Standard 4.0 formula, instant results. No upload—runs locally in your browser. Free, no signup.
• Grass Seed CalculatorFree grass seed calculator: lawn area and seeding rate → pounds or kilograms of seed with optional buffer. New lawn and overseed presets. Runs locally in your browser.
• Gravel CalculatorFree gravel calculator: path or driveway area and depth → cubic yards, cubic feet, and bag estimates with compaction buffer. Runs locally in your browser.
• Gutter CalculatorFree gutter calculator: eave length or perimeter → linear feet and 10 ft section counts with overlap buffer. Runs locally in your browser.
• Heart Rate Zone CalculatorFree heart rate zone calculator: Karvonen or 220−age, five zones in bpm—fat burn, cardio, threshold, HIIT. Runs locally; never uploaded.
• Heat Pump Size CalculatorFree heat pump size calculator: room dimensions → tons with cooling and heating BTU/hr estimates. Runs locally in your browser.
• Hot Water Flow CalculatorFree hot water flow calculator: simultaneous fixtures → peak GPM and tankless BTU/hr at your temperature rise. Runs locally in your browser.
• Hourly Pay Calculator — Gross Pay, Overtime & Pay PeriodsConvert hourly wage to daily, weekly, monthly & yearly gross pay. Overtime 1.5×, job compare, tax estimate. No upload—runs locally in your browser. Free.
• Ideal Weight CalculatorEstimate ideal weight using Devine, Robinson, Miller, and Hamwi formulas and compare the output range in one place. Runs locally in your browser when supported—no upload required for normal use.
• Insulation CalculatorFree insulation calculator: area + sq ft per batt bag → bags to buy with waste buffer. Attic, wall, and crawl presets with opening deductions. Runs locally in your browser.
• Landscape Fabric CalculatorCalculate landscape fabric and whole rolls from bed size, roll width and length, seam overlap, and waste. Supports multiple beds. Free, runs in your browser.
• Landscape Rock CalculatorFree landscape rock calculator: bed size or tree ring and depth → cubic yards, ton estimates, bags, and bulk vs bag guidance. River rock presets, round bed mode, order buffer. Runs locally in your browser.
• LCM CalculatorCalculate the least common multiple of two or more integers with formula-based steps and prime factorization guidance. Runs locally in your browser when supported—no upload required for normal use.
• Lean Body Mass Calculator — LBM From Body Fat or HeightCalculate lean body mass from body fat % or Boer, James, and Hume formulas. Runs locally in your browser—never uploaded. Free LBM & BMR estimates.
• Logarithm Calculator — log₁₀, ln & Custom BaseFree logarithm calculator: log base 10, natural log (ln), log₂, or any custom base b for positive x. Runs in your browser—never uploaded.
• Macro CalculatorEstimate daily macros from BMR and TDEE, then split calories into protein, carbs, and fats for fat loss, maintenance, or muscle gain. Runs locally in your browser when supported—no upload required for normal use.
• Meal Cost Calculator — Recipe & Cost per ServingFree meal cost calculator: unit-labeled ingredients, waste %, weekly meal plan, food-cost target & CSV export. Runs locally—never uploaded.
• Mean Median Mode CalculatorCompare mean, median, and mode from one dataset. See how each central-tendency measure describes your numbers when outliers or skew matter. Runs locally in your browser when supported—no upload required for normal use.
• Meat Thaw Time CalculatorFree meat thaw calculator: frozen weight → refrigerator or cold-water thaw hours — 12 lb turkey ≈ 57.6 hours (~2.4 days) in the fridge. Runs locally in your browser.
• Metal Roofing CalculatorFree metal roofing calculator: roof area and sq ft per panel → panel counts with waste buffer. Standing seam presets. Runs locally in your browser.
• Monthly Budget CalculatorFree monthly budget calculator — track income and categorized expenses to see surplus/deficit and 50/30/20 splits. Plan savings targets. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Mulch CalculatorFree mulch calculator: bed size or square footage and depth → cubic yards, cubic feet, liters, and bag counts. Depth presets, coverage tables, optional buffer. Imperial or metric. Runs locally in your browser.
• Online CalculatorFast keyboard-friendly calculator for +, −, ×, ÷, %, and parentheses. No upload—runs locally in your browser. Free, instant results.
• Oven Temperature Converter CalculatorFree oven temperature converter: Fahrenheit, Celsius, and UK gas mark for baking — 350°F → 177°C, Gas 4. Runs locally in your browser.
• Overtime Pay Calculator — 1.5×, Double-Time & Gross PayCalculate overtime pay at 1.5× or 2×: enter hourly rate, regular hours, and OT hours for gross weekly pay. Runs locally in your browser—never uploaded. Free.
• Ovulation Calculator — Fertile Window & Ovulation CalendarEstimate ovulation day and fertile window from last period date and cycle length. Calendar + 3-cycle forecast. Runs locally in your browser—never uploaded. Free.
• Paint CalculatorFree paint calculator: enter wall area, coverage from your can, and coats → gallons or liters to buy. Room presets, door/window deductions, waste buffer, can round-up. Runs locally in your browser.
• Paver CalculatorFree paver calculator: patio area, paver size, and cut waste → paver count, boxes, and pallets. Backyard patio presets, ICPI waste guidance, imperial or metric. Runs locally in your browser.
• Percentage CalculatorWhat is 20% of 500? Percent increase, decrease, difference, reverse %, markup & margin—runs locally in your browser, no upload. Copy results or share a link.
• Permutation Calculator — nPr (Ordered Arrangements)Calculate permutations nPr = n!/(n−r)! when order matters—5P2, 10P3, 26P3 & more. Runs locally in your browser, no upload. Exact results up to n=500.
• PEX Pipe CalculatorFree PEX pipe calculator: run length or perimeter → linear feet and coil counts with fittings buffer. Runs locally in your browser.
• Pipe Sizing CalculatorFree pipe sizing calculator: fixture counts → WSFU and DFU totals with supply and drain pipe size recommendations. Runs locally in your browser.
• Pipe Volume CalculatorFree pipe volume calculator: inside diameter and length → gallons, liters, and water weight in the pipe. Imperial and metric. Runs locally in your browser.
• Pizza Dough CalculatorFree pizza dough calculator: split total dough into equal balls or compute from flour and hydration — 1000 g ÷ 4 = 250 g per ball. Runs locally in your browser.
• Plant Spacing CalculatorFree plant spacing calculator: bed size and row/plant spacing → total plants for grid layouts. Tomato, lettuce, and square-foot presets. Runs locally in your browser.
• Pregnancy Due Date CalculatorEstimate pregnancy due date from the first day of your last menstrual period (LMP) with a simple 40-week calculation. Runs locally in your browser when supported—no upload required for normal use.
• Prime Number Calculator — Factor Tree, Sieve & nth PrimeSix modes: check, factor tree, list, range, nth, random. Sieve animation, Miller–Rabin to 10¹², export TXT/CSV—runs locally.
• Probability Calculator — Independent Events & ComplementsCalculate P(A), complements, P(A and B), and P(A or B) for independent events. No upload—runs locally in your browser. Free, instant.
• Profit Margin CalculatorFree profit margin calculator — compute profit, margin %, and markup from cost and selling price, or find price for a target margin. Runs locally. No signup.
• Protein Intake CalculatorEstimate daily protein requirements based on body weight, activity level, and fitness goal. Results in grams per day and per meal. Runs locally in your browser when supported—no upload required for normal use.
• Raised Bed Soil CalculatorFree raised bed soil calculator with mix splits (60/40, Mel's Mix), round & rectangular beds, bulk vs bag guidance, weight estimates, cubic yards, and bag counts. Runs locally in your browser.
• Ratio CalculatorFree ratio calculator & ratio solver — simplify ratios (12:18 → 2:3), compare equivalence, simplify aspect ratios (1920×1080 → 16:9). Runs locally; data stays on your device.
• Recipe Scaler CalculatorFree recipe scaler: original and new servings → scale factor and ingredient amounts. Double, halve, or custom serving math. Runs locally in your browser.
• Retaining Wall Block CalculatorFree retaining wall block calculator: wall length, height, and block size → blocks to order, courses per row, and cut buffer. Garden terrace presets for 16×8 in blocks. Imperial or metric. Runs locally in your browser.
• Rice to Water Ratio CalculatorFree rice to water ratio calculator: cups of dry rice and rice type → how much water for stovetop cooking. White, jasmine, basmati, brown, and sushi presets.
• Roof Area CalculatorFree roof area calculator: building footprint and pitch → total roof surface sq ft. Rectangle or area input with slope multiplier. Runs locally in your browser.
• Roof Pitch CalculatorFree roof pitch calculator: rise and run → pitch ratio (X/12), angle in degrees, and footprint area multiplier. Residential pitch presets. Runs locally in your browser.
• Roofing Material CalculatorFree roofing material calculator: roof area → shingle bundles and underlayment rolls with waste buffer. Full takeoff presets. Runs locally in your browser.
• Running Pace Calculator — Pace, Time & Race SplitsFree running pace calculator: pace, finish time, or distance from any two values. Min/km & min/mile, race presets, splits—runs locally in your browser, never uploaded.
• Salary After Tax CalculatorEstimate take-home pay from salary using simplified tax brackets and standard deductions (US/UK/CA/AU + custom). Shows effective and marginal rates. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Salary to Hourly CalculatorConvert salary to hourly, daily, weekly, and monthly pay using the 2,080-hour baseline, then adjust for weekly hours and PTO for a true hourly rate. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Sand CalculatorFree sand calculator: patio footprint and bedding depth → cubic yards, bags, and bulk vs bag guidance. Paver bedding presets, round patio mode, order buffer. Imperial or metric. Runs locally in your browser.
• Scientific CalculatorUse a scientific calculator for trigonometry, logarithms, powers, roots, and constants with DEG/RAD support and instant browser-based results. Runs locally in your browser when supported—no upload required for normal use.
• Septic Tank CalculatorFree septic tank calculator: bedrooms or occupants → recommended tank gallons with daily flow estimate. Runs locally in your browser.
• Sleep Cycle CalculatorFind the best bedtime or wake-up time based on 90-minute sleep cycles. Minimize sleep inertia by waking at the end of a cycle. Runs locally in your browser when supported—no upload required for normal use.
• Sod CalculatorFree sod calculator: lawn area and pallet size → pallets and rolls to order. Lawn presets, trim buffer, sq ft per pallet from your farm tag. Imperial or metric. Runs locally in your browser.
• Soffit CalculatorFree soffit calculator: eave length and soffit depth → sq ft to cover with optional 4×8 sheet counts. Runs locally in your browser.
• Space Heater Cost CalculatorFree space heater cost calculator: heater watts and daily use → kWh and operating cost at your electric rate. Runs locally in your browser.
• Square Root CalculatorCalculate square roots, cube roots, and nth roots with decimal precision and simplified radical form for integers. Runs locally in your browser when supported—no upload required for normal use.
• Standard Deviation CalculatorCalculate population or sample standard deviation, see variance, and understand dataset spread with a simple variance-to-standard-deviation workflow. Runs locally in your browser when supported—no upload required for normal use.
• Steps to Distance CalculatorConvert steps to km or miles using step length, height, or averages. Reverse mode included—free, runs locally in your browser.
• Study Time Calculator — Daily & Weekly Study Hours by SubjectSplit total study hours across subjects, weeks, and study days—or plan from an exam date. Free daily study targets in your browser; no signup.
• Sump Pump CalculatorFree sump pump calculator: basement sq ft and head height → recommended GPM capacity with heavy-rain margin. Runs locally in your browser.
• Tile CalculatorFree tile calculator: floor area + tile size → tiles and boxes to buy with waste buffer. Bath and kitchen presets, 10–15% waste, imperial and metric. Runs locally in your browser.
• Time and a Half CalculatorFree time-and-a-half calculator — enter your regular hourly rate and overtime hours to calculate pay at 1.5× rate. Instant results for payroll and wage verification. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Tip CalculatorFree tip calculator — find tip amount, bill + tip total, and per-person share. Presets for common percentages (10%, 15%, 20%), custom %, and equal split. Runs in your browser. No signup.
• Topsoil CalculatorFree topsoil calculator: lawn or bed dimensions and fill depth → cubic yards, cubic feet, liters, and bags. Leveling and new bed presets. Runs locally in your browser.
• Turkey Serving CalculatorFree turkey serving calculator: guest count and lb per person → total turkey weight to buy, with optional leftovers buffer. Runs locally in your browser.
• Unit Price CalculatorFree unit price calculator: divide price by quantity to compare cost per unit across package sizes. Private, instant, no signup. Runs locally in your browser when supported—no upload required for normal use.
• Voltage Drop CalculatorFree voltage drop calculator: amps, AWG, and run length → percent voltage loss. Extension cord and branch-circuit checks. Runs locally in your browser.
• Wallpaper CalculatorFree wallpaper calculator: room size, roll dimensions, and pattern repeat → rolls to buy. Room and accent-wall presets, waste buffer. Runs locally in your browser.
• Water Heater CalculatorFree water heater calculator: household size → tank gallon size or tankless GPM and BTU/hr. Tank and tankless modes. Runs locally in your browser.
• Water Intake CalculatorEstimate daily hydration using a weight-based formula with activity adjustments, then view results in liters, cups, and milliliters. Runs locally in your browser when supported—no upload required for normal use.
• Window AC Cost CalculatorEstimate window AC running cost from watts or BTU÷EER, hours/day, and $/kWh — daily, monthly, and seasonal. Runs locally in your browser.
• Wire Gauge CalculatorFree wire gauge calculator: load watts or amps → minimum copper AWG with continuous-load sizing. 60°C NM-B ampacity reference. Pair with breaker and voltage drop tools. Runs locally in your browser.
• Work Hours Calculator — Net Hours, Breaks & Decimal TimeCalculate net work hours from clock-in, clock-out, and unpaid breaks—decimal output for timesheets. No upload: runs locally in your browser. Free.
• Yeast Converter CalculatorFree yeast converter: swap active dry, instant, and fresh yeast by potency — 2 tsp active dry → 1.5 tsp instant. Runs locally in your browser.
• Zakat CalculatorEstimate zakat from cash, metals, and assets minus short-term debts—nisab via 85g gold or 595g silver × your price per gram, then 2.5% if due. Rules vary. No signup. Runs locally in your browser when supported—no upload required for normal use.

Read and clean structured data: JSON/XML/YAML formatters, URL and JWT parsers, regex testers, SQL formatters, UUID and hash generators, QR codes, API keys, and similar—all in one hub. After generating values, use the same category to validate, diff, or pretty-print the result.

• .env ParserFree .env file parser — paste any .env file and extract all environment variables as structured JSON or YAML. Useful for config migration and debugging. No signup needed. Runs locally in your browser when supported—no upload required for normal use.
• API Key GeneratorGenerate a secure random API key or webhook secret in your browser. Hex, Base64url, or alphanumeric. Keys stay local—not a Stripe or OpenAI credential.
• API Mock GeneratorDesign a mock REST response in your browser—JSON body, status, headers, and delay. Copy Express or MSW snippets. Free, no signup. Does not host a live API URL.
• Base64 Encoder & DecoderEncode or decode Base64 online: text, files, images, Base64URL, and data URIs. UTF-8 safe. Runs in your browser—no upload, no signup.
• Code Minifier & BeautifierFree code minifier and beautifier — minify JavaScript, HTML, and CSS for production or beautify minified code for readability. Supports ES6+ and modern CSS syntax. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Color PickerFree online color picker — choose any color and instantly get HEX, RGB, HSL, HSB, and CMYK values. Copy color codes for CSS, design tools, and development. No signup. Runs locally in your browser when supported—no upload required for normal use.
• CORS Header GeneratorFree CORS header generator — configure Access-Control-Allow-Origin, methods, headers, and credentials. Preview the full CORS response header block instantly. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Cron Expression GeneratorBuild cron schedules with live preview, timezone next runs, and platform snippets for Linux, Quartz, K8s, GitHub Actions & AWS. Browser-local.
• CSS FormatterFormat CSS with consistent indentation and line breaks. Local beautification for readable stylesheets and git diffs. Runs locally in your browser when supported—no upload required for normal use.
• cURL to Fetch ConverterFree cURL to fetch converter — paste any cURL command and instantly get the equivalent JavaScript fetch() code with all headers, methods, and body included. No signup needed. Runs locally in your browser when supported—no upload required for normal use.
• Domain ExtractorExtract deduplicated domains from logs, emails, and mixed text. URLs, markdown, hostnames. CSV/JSON export. No upload—100% browser-based.
• Git Commit GeneratorFree Git commit message generator — build Conventional Commits (feat, fix, chore, docs, refactor) with scope, breaking change flag, and body. Copy the formatted message instantly. No signup. Runs locally in your browser when supported—no upload required for normal use.
• GraphQL FormatterFree GraphQL formatter — paste queries, mutations, or schema definitions and instantly get properly indented, beautified output with syntax validation. Perfect for debugging. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Hash GeneratorCompute MD5, SHA-1, SHA-256 and other digests from text locally. One-way hashing for checksums—not password storage.
• HTML Entity Encoder & DecoderFree HTML entity encoder—convert &, <, >, and quotes to &amp;, &lt;, &gt; and decode entities back. XSS-safe for templates. Runs locally in your browser; no upload.
• HTML FormatterFree HTML formatter—beautify minified markup with 2 or 4 space indent, minify for production. Runs locally in your browser; no upload or signup.
• HTTP Cookie Parser — Parse, Decode & Build Cookie StringsPaste any HTTP Cookie header, Set-Cookie header, or curl command to extract name, value, domain, path, expiry, Secure, HttpOnly, and SameSite flags. Build and export cookies too. No signup. Runs locally in your browser when supported—no upload required for normal use.
• HTTP Header GeneratorFree HTTP header generator — build Content-Type, Cache-Control, CORS, Authorization, and security headers with correct syntax. Copy for NGINX, Apache, or API responses. No signup. Runs locally in your browser when supported—no upload required for normal use.
• IP ConverterFree IPv4 converter — dotted decimal, 32-bit integer, hex, and binary octets from one paste. Batch CSV export. Runs in your browser. No signup.
• JSON Diff ToolFree JSON diff & compare — structural side-by-side diff, ignore paths, array modes, RFC 6902 patch and merge patch export. Runs locally in your browser—no upload.
• JSON FormatterFree JSON formatter — paste minified or messy JSON and instantly get beautified, indented output with syntax highlighting and error detection. Browser-based, no server upload. Runs locally in your browser when supported—no upload required for normal use.
• JSON Path FinderFree JSON path finder — click any value in a formatted JSON tree to instantly copy its JSONPath expression. Ideal for navigating deep API payloads and config files. No signup. Runs locally in your browser when supported—no upload required for normal use.
• JSON Schema GeneratorFree JSON Schema generator — infer Draft 2020-12 from sample JSON with TypeScript, Zod, Yup, and OpenAPI exports. No signup. Runs locally in your browser—no upload required.
• JSON ValidatorValidate JSON syntax and find errors instantly. Get clear error messages with line and column details. Runs locally in your browser when supported—no upload required for normal use.
• JWT Decoder — Decode & Inspect JSON Web TokensDecode JWT header and payload, check exp/iat claims, encode HS256 test tokens. No upload—runs in your browser locally. Free, no signup.
• JWT GeneratorCreate and sign JSON Web Tokens (JWTs) online with HS256, HS384, or HS512. Enter header, payload, and secret to generate a signed JWT instantly — fully browser-based. Runs locally in your browser when supported—no upload required for normal use.
• localStorage Viewer & InspectorFree localStorage viewer: search keys, JSON preview, edit, export, and bulk delete for this origin. Runs locally in your browser—never uploaded.
• Markdown EditorFree online Markdown editor — write Markdown with syntax highlighting and see the rendered HTML preview in real time. Export as HTML or copy formatted output. No signup required. Runs locally in your browser when supported—no upload required for normal use.
• Number Base ConverterFree number base converter: binary, decimal, octal, hex, and custom bases 2–36. Live convert with BigInt for large integers. Browser-local, no signup.
• QR Code GeneratorFree QR code generator — create scannable QR codes from URLs, plain text, email, phone numbers, or Wi-Fi credentials. Download as PNG or SVG. No signup, no limits, fully browser-based. Runs locally in your browser when supported—no upload required for normal use.
• Query String ParserFree query string parser — paste any URL query string and instantly extract all parameter key-value pairs into a readable JSON or table format. Handles URL encoding. No signup required. Runs locally in your browser when supported—no upload required for normal use.
• Random Number GeneratorFree random number generator — Web Crypto integers or decimals, no-repeat draws, dice, coin flip, and list picker. Copy or CSV. Runs locally in your browser.
• Regex TesterFree regex tester — highlight matches, capture groups, flags, and replace preview. JavaScript RegExp in your browser; patterns and text stay on your device, nothing uploaded.
• Screen Resolution CheckerFree screen resolution checker — instantly see your screen resolution, viewport size, device pixel ratio (DPR), and current CSS breakpoint. Useful for responsive design testing. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Semver CalculatorFree semver calculator — compare two version strings, bump major, minor, or patch components, and sort version lists following SemVer 2.0 rules. Essential for npm, Cargo, and API release management. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Semver CheckerFree semver range checker — test whether a version string (e.g. 2.3.1) satisfies a range expression (^2.0.0, >=1.5.0 <3.0.0, ~2.3.x) following npm / SemVer 2.0 rules. Useful before upgrading package dependencies. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Semver TesterFree SemVer format validator — check whether a version string follows Semantic Versioning 2.0 (major.minor.patch with optional pre-release and build metadata). Catches leading zeros, missing patch components, and invalid identifiers instantly. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Session Storage ViewerFree sessionStorage viewer — inspect, add, edit, and delete sessionStorage key-value pairs in your browser. Useful for debugging web apps and testing session data. No signup.
• SQL FormatterFormat SQL with indented clauses and keyword casing. Dialect-aware beautification runs locally—not on a server.
• SQL Query BuilderFree visual SQL query builder — select table, columns, WHERE conditions, JOIN type, and ORDER BY using a form and get the generated SELECT query instantly. No signup required. Runs locally in your browser when supported—no upload required for normal use.
• String EscaperFree string escaper — escape or unescape strings for JavaScript, HTML, JSON, regex, and URL contexts with one click. Handles backslashes, quotes, newlines, and special characters. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Text Diff ToolCompare two plain-text inputs line by line and highlight changes. Local diff for logs and copy—not JSON structure. Runs locally in your browser when supported—no upload required for normal use.
• Text to Binary ConverterFree text to binary converter — encode any text to 8-bit binary (0s and 1s) and decode binary back to text. Supports ASCII and UTF-8 encoding. Instant, browser-based, no signup. Runs locally in your browser when supported—no upload required for normal use.
• Text to Hex — UTF-8 Bytes, Hex Dump, Byte InspectorUTF-8 byte hex, code point & Latin-1 modes, byte inspector, hex dump, binary/Base64 compare—browser-local with share URL.
• TOML FormatterFormat and validate TOML config files like Cargo.toml and pyproject.toml instantly in your browser. Syntax highlighting, error detection, no upload required.
• URL BuilderFree URL builder — add a base URL, append query parameters, auto-encode values, and copy the complete URL string. Perfect for API testing, UTM links, and affiliate tracking. No signup. Runs locally in your browser when supported—no upload required for normal use.
• URL Encoder & DecoderFree URL encoder decoder for query values and full URLs—encodeURIComponent & encodeURI. Percent-encode or decode instantly in your browser; never uploaded.
• URL Parser — Break Down URL ComponentsParse any URL into scheme, host, port, path, query params, and hash. No upload—runs in your browser. Free for API and OAuth debugging.
• User Agent ParserFree user agent parser — paste any UA string and instantly identify the browser, version, operating system, device type, and rendering engine. No signup required. Runs locally in your browser when supported—no upload required for normal use.
• UUID GeneratorFree UUID generator: v4, v7 & v1 GUIDs in your browser—bulk up to 1,000, validate, export JSON/CSV. crypto.randomUUID; never uploaded.
• What Is My Browser?See your browser name and version in one second—plus OS, screen size, and user agent. Copy for support; runs locally with nothing uploaded.
• YAML Formatter & ValidatorFree YAML formatter and validator — paste YAML to fix indentation, validate syntax, and detect errors instantly. Supports YAML 1.2. Perfect for Docker Compose and Kubernetes manifests. No signup. Runs locally in your browser when supported—no upload required for normal use.

Plain text workflows: counting words, fixing case, comparing drafts, generating placeholders or passwords, light editing in the browser. Reach for these when your input is copy-paste text rather than a binary file.

• Bold Text GeneratorMake bold Unicode text and copy-paste it into Instagram, Discord, LinkedIn & more. Free bold, italic, sans & script—runs in your browser.
• Character CounterFree character counter — count characters with and without spaces for Twitter/X, SMS, meta tags, and ad headlines. Platform limit reference. Runs locally in your browser.
• Lorem Ipsum GeneratorFree Lorem Ipsum generator — create placeholder text by paragraphs, word count, or byte length for wireframes, mockups, and UI design. Classic or custom Lorem Ipsum. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Online NotepadFree online notepad — write and save notes with autosave to your browser's local storage. No account needed, no sync. Notes stay in your browser storage for normal use. Distraction-free writing tool. Runs locally in your browser when supported—no upload required for normal use.
• Password GeneratorFree password generator — create strong random passwords with custom length and character sets: uppercase, lowercase, numbers, and symbols. Copy instantly. Fully browser-based. Runs locally in your browser when supported—no upload required for normal use.
• Random String GeneratorFree random string generator — choose length and character set (alphanumeric, hex, base64, symbols) to generate cryptographically random strings. Copy or download instantly. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Random Word Generator — Writing Prompts & GamesGenerate random words for writing prompts, games & brainstorming—filter by category, difficulty & letter. Runs locally in your browser; no upload, no signup.
• Reading Time CalculatorFree reading time estimator — calculate reading time for articles and blogs (word count ÷ WPM), speech time, and audiobook length. Paste text or enter count; runs locally, data stays on your device.
• Remove Extra SpacesFree whitespace cleaner — strip multiple spaces, trim leading and trailing whitespace, fix line breaks, and clean text formatting instantly. Paste and copy in seconds. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Text Case ConverterFree text case converter — convert to UPPERCASE, lowercase, Title Case, camelCase, snake_case, kebab-case, and sentence case instantly. One click, no signup, browser-based. Runs locally in your browser when supported—no upload required for normal use.
• Word CounterFree word counter — live word, sentence, and paragraph counts plus reading time for essays, blogs, and SEO drafts. Runs locally in your browser.
• Word Frequency CounterFree word frequency counter — analyze word usage in your text, see keyword density, and spot overused or underused terms. Essential for SEO audits and content optimization. No signup. Runs locally in your browser when supported—no upload required for normal use.

Anything tied to a calendar or a clock: adding days, age in years/months, time zones, work hours, or planetary time quirks. If the question is “when” or “how long,” this bucket usually beats a general-purpose calculator.

• Age CalculatorHow old am I? Exact age in years, months, and days from date of birth—plus age as of any date, days lived, and next birthday. Free, private, no signup.
• Age on Other Planets Calculator — How Old Would You Be on Mars?Enter your birth date to see your age on Mars, Mercury, Jupiter, and every planet—plus Earth days lived and your next planetary birthday. Free, private.
• Date Calculator — Add, Subtract & Days Between DatesAdd or subtract days, weeks, months, or years from any date. Days-between mode included. No upload—runs locally in your browser. Free, no signup.
• Employee Hours TrackerFree employee hours tracker — log start/end times, breaks, and overtime for multiple employees. Calculate weekly totals and prepare payroll summaries. No signup required. Runs locally in your browser when supported—no upload required for normal use.
• Freelance Hours CalculatorFree freelance hours calculator — log start and end times for multiple projects to calculate total billable hours and estimate earnings at your hourly rate. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Hours CalculatorFree hours calculator — calculate the total time between any two times, including overnight spans. See results in hours and minutes or decimal format. No signup required. Runs locally in your browser when supported—no upload required for normal use.
• Overtime Hours CalculatorFree overtime hours calculator — enter daily hours worked and your regular schedule limit to calculate total overtime hours. Supports daily and weekly overtime rules. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Pet Age CalculatorFree pet age calculator — convert your dog or cat's age into equivalent human years using breed-adjusted formulas. Great for understanding your pet's life stage. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Planet Distance ConverterFree planet distance converter — convert between astronomical units (AU), kilometers, and miles for solar system distances. See how far each planet is from the Sun. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Planet Size ComparisonCompare Mercury–Pluto diameters, masses & volumes vs Earth. NASA reference charts, ratios, shareable URLs—runs locally in your browser, no signup or upload.
• Planetary Day ConverterConvert Mars sols, Jupiter days, and planet rotations to Earth days. NASA rotation data, instant ratios—runs locally in your browser, no signup or upload.
• Planetary Year ConverterConvert Earth years to orbital years for all planets. A Mars year is 1.88 Earth years; a Neptune year is 165 Earth years. Browser-based, no signup, uses NASA IAU orbital data. Runs locally in your browser when supported—no upload required for normal use.
• Sunrise & Sunset on Other PlanetsHow long does daylight last on Mars, Venus, or Jupiter? Explore sunrise and sunset times based on each planet's rotation period and axial tilt. Browser-based, no signup. Runs locally in your browser when supported—no upload required for normal use.
• Time CalculatorFree time calculator — add or subtract hours, minutes, and seconds, or calculate the exact duration between two times. Handles overnight spans automatically. No signup required. Runs locally in your browser when supported—no upload required for normal use.
• Time Duration CalculatorFree time duration calculator — calculate the exact duration between two dates or times in days, hours, minutes, and seconds. No signup required. Runs locally in your browser when supported—no upload required for normal use.
• Time Zone Converter — Convert Time Between CitiesConvert time between cities and IANA time zones with DST handled automatically. No upload—runs locally in your browser. Free, no signup.
• Unix Timestamp Converter — Epoch to Human DateConvert Unix epoch to readable dates and back—seconds or milliseconds, UTC and local. No upload: runs in your browser. Free, no signup.
• Weight on Other PlanetsHow much would you weigh on Mars (38% of Earth), Jupiter (2.5×), or the Moon (16.5%)? Free weight on other planets calculator using NASA surface gravity values. No signup. Runs locally in your browser when supported—no upload required for normal use.

Front-end craft: WCAG contrast, palettes, gradients, shadows, Tailwind picks, favicons, and other CSS you can copy into a project. This row is about layout and styling code.

• Clip Path GeneratorFree CSS clip-path generator — build polygon, circle, and ellipse shapes visually with draggable points and copy the clip-path CSS property instantly. No signup needed. Runs locally in your browser when supported—no upload required for normal use.
• Color Contrast CheckerFree color contrast checker — test text and background color combinations for WCAG AA (4.5:1) and AAA (7:1) compliance. Essential for accessible web design. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Color Palette GeneratorFree color palette generator — create complementary, analogous, triadic, and monochromatic palettes from any base color. Copy HEX codes instantly. No signup. Runs locally in your browser when supported—no upload required for normal use.
• CSS Border Radius GeneratorFree CSS border radius generator with live preview — per-corner controls, pill & circle presets, blob mode, px/%/rem/em. Copy CSS, Tailwind, or SCSS. No signup. Runs locally in your browser.
• CSS Box Shadow GeneratorFree CSS box shadow generator with live preview — multi-layer controls, inset, Soft/Material-style presets, blur & spread. Copy CSS, inline, or Tailwind. No signup. Runs locally in your browser.
• CSS Button GeneratorFree CSS button generator — design custom buttons with gradients, shadows, border radius, and hover effects using visual controls. Copy the CSS and HTML instantly. No signup. Runs locally in your browser when supported—no upload required for normal use.
• CSS Clamp CalculatorFree CSS clamp() calculator — generate responsive clamp() values for fluid typography and spacing. Enter minimum, maximum, and viewport sizes for instant CSS output. No signup. Runs locally in your browser when supported—no upload required for normal use.
• CSS Filter GeneratorFree CSS filter generator — create blur, brightness, contrast, grayscale, hue-rotate, and other filter effects with live preview. Copy the CSS filter property. No signup. Runs locally in your browser when supported—no upload required for normal use.
• CSS Gradient GeneratorFree CSS gradient generator — create linear and radial gradients with custom colors, stops, and directions. Live preview and one-click CSS copy. No signup required. Runs locally in your browser when supported—no upload required for normal use.
• CSS Grid Layout GeneratorFree CSS Grid generator — define rows, columns, and named grid areas visually and copy the generated CSS grid-template code. Perfect for responsive web layouts. No signup required. Runs locally in your browser when supported—no upload required for normal use.
• CSS Unit ConverterFree CSS unit converter — convert px, rem, em, vw, and vh with a custom root font size. See all CSS unit equivalents at once for responsive design. No signup required. Runs locally in your browser when supported—no upload required for normal use.
• Favicon GeneratorFree favicon generator — create website favicons in 16×16, 32×32, 48×48, and 64×64 PNG sizes from text, emoji, or an uploaded image. Download as .ico or individual PNG files. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Glassmorphism GeneratorBuild frosted glass CSS with WCAG contrast checker, layer composer, VisionOS/Fluent presets, and full export—CSS, Tailwind, tokens, share URL. Blur 0–40px. Browser-only, no signup.
• Image Blend Mode ToolFree CSS mix-blend-mode tool—preview overlays, before/after split, download PNG, copy CSS/HTML/Tailwind/React. Runs locally; no upload or signup.
• Neumorphism GeneratorFree neumorphism generator — set element size, border radius, distance, blur, and intensity to create soft UI shadows. Preview flat, pressed, and raised styles. Copy CSS instantly. No signup. Runs locally in your browser when supported—no upload required for normal use.
• Spacing Scale GeneratorFree spacing scale generator — create 4px, 8px, or custom-base spacing systems and export them as CSS variables, Tailwind config, or design token JSON. No signup required. Runs locally in your browser when supported—no upload required for normal use.
• SVG Icon CustomizerFree SVG icon customizer — adjust icon size, fill color, stroke width, and opacity with a live preview. Download the customized SVG or copy the inline code. No signup required. Runs locally in your browser when supported—no upload required for normal use.
• SVG to JSXFree SVG to JSX converter — paste SVG markup and instantly get React-compatible JSX with camelCase attributes, cleaned props, and self-closing tags. No signup needed. Runs locally in your browser when supported—no upload required for normal use.
• Tailwind Cheat SheetInteractive Tailwind CSS reference and class composer—search thousands of utilities with CSS mappings, preview dark/responsive states, copy HTML/CSS, and export to Tailwind Play. Browser-local, no signup.
• Text Shadow & Glow GeneratorFree CSS text shadow generator — create single or multi-layer text shadows and neon glow effects with a live preview. Copy ready-to-paste CSS code instantly. No signup needed. Runs locally in your browser when supported—no upload required for normal use.
• Typography Scale GeneratorFree typography scale generator—major third, perfect fourth, golden ratio. Export CSS variables & JSON tokens. Runs in your browser; never uploaded.

Preview STL, glTF, OBJ, and related assets in the browser, tweak shaders, capture views. Useful for quick inspection; heavy modeling still belongs in desktop 3D software.

• 360 Image Viewer Online — Look Around 360 Photos, No UploadOpen a 360 photo in your browser and drag to look around. Zoom and fullscreen. Your file stays on this device — nothing is uploaded. Free, no account.
• 3D Model ViewerOpen GLB, GLTF, STL, or OBJ in your browser. Orbit, wireframe, lighting, and mesh stats. Free — no install, no signup. The file never leaves this device.
• Convert 3D Model to PNG OnlineConvert a GLB, STL, or OBJ to PNG or JPG in your browser. Transparent PNG and square thumbnails. The file never leaves this device.
• GLSL Shader EditorFree browser-based GLSL shader editor — write fragment and vertex shaders with real-time WebGL rendering. Includes u_time, u_resolution, and u_mouse uniforms for animated and interactive effects. Syntax highlighting, error console, and built-in examples. No install required. Runs locally in your browser when supported—no upload required for normal use.